study comparing effects of lanthanum carbonate versus calcium acetate versus dietary phosphorus restriction

Conditions: Chronic Kidney Disease

Summary: objective: to examine the effects of three commonly applied treatments of disordered phosphorus homeostasis on biochemical markers and vascular characteristics in patients with moderate and advanced non-dialysis dependent chronic kidney disease.

approximately 120 qualified patients from our medical center, who have been diagnosed with mild to moderate chronic kidney disease (estimated gfr 15-60 ml/min), will be enrolled. after informed consent, qualified subjects will be randomized into 3 arms in a 1:1:1 ratio: lanthanum carbonate, calcium acetate, and dietary modification. the maximum length of treatment is 12 months. dose of intervention will be adjusted based on changes in biochemical parameters. primary end points are changes in serum phosphorus, urine phosphorus, serum parathyroid hormone, coronary artery calcification, aortic pulse velocity and flow mediated vasodilation.

Eligibility criteria:
inclusion criteria: * male or female ckd patients \> 18 years old * patients should be willing and able to provide written informed consent and hipaa authorization to participate in study * chronic kidney disease stage 3 or 4 per k-doqi guidelines: estimated glomerular filtration rate (egfr) of 15-60 ml/.min/1.73m2 by using modified mdrd equation. * serum phosphorus \>4.6 mg/dl or plasma intact pth (ipth) level above 65 pg/ml or tubular reabsorption of phosphorus (trp) \<80%. * a negative pregnancy test prior to enrollment in female patients, unless the patient is 2 years postmenopausal, or has had a documented tubal ligation or total hysterectomy. * patients need to be off any phosphorus binders for 4 weeks prior to screening * stable dose of vitamin d products for 4 weeks in patients receiving such agents. dose changes in patients receiving stable and initiation of vitamin d products in patients previously not treated will not be permitted during study exclusion criteria: * women who are pregnant, capable of becoming pregnant and not participating in an acceptable form of birth control, or who are breast feeding * patients currently participating in a clinical trial with another investigational drug or device or who have receiving an investigational drug or device within 30 days of enrollment in this study * major surgery within 2 month prior to enrollment in study or planned surgery while the patient is in the study, other than dialysis vascular access surgery. * presence of coronary stents, artificial heart valves or pacemakers, and history of cabg * patients with active infections requiring ongoing treatment * patients who have had a malignancy (except for non-melanoma cancer of the skin) unless the patient has received curative treatment and has been disease free for \>2 years * patient who the investigator determines has a medical status that would preclude the patient's participation in the study * patients on hemodialysis (hd) or peritoneal dialysis (pd) * patients with a functional renal transplant * patients with allergies to study drugs * patients with serum calcium \>10.7 mg/dl.

Keywords: kidney disease hyperphosphatemia parathyroid hormone